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visits member for 3 years, 9 months
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Started programming on a ZX spectrum in the 80's and have moved through Assembly, Turbo Pascal, C++, C#, Fortran. My main area of focus is engineering and scientific computing like numerical methods and 3D graphics.


Aug
1
comment How far do atoms move in a wire when whirling it horizontally?
Please try to use math formatting for better readability.
Aug
1
answered Which Force would help find the mass?
Aug
1
comment How to measure trajectory regularity?
This is a Mathematics problem. Measure the total length with different length yardsticks and you will get a more pronounced effect with the irregular pattern. en.wikipedia.org/wiki/Fractal_dimension
Aug
1
comment How to measure trajectory regularity?
See fractal dimension. The top one has $f \approx 1$ and the the bottom one $f>1$.
Jul
31
comment Why do ships lean to the outside, but boats lean to the inside of a turn?
So the quick answer here is because they are designed to do exactly this. Btw, cool pictures.
Jul
31
comment Calculating force of a car
possible duplicate of How to get distance when acceleration is not constant?
Jul
31
comment Calculating force of a car
You need to explain what is wrong with the results.
Jul
31
revised Moment of inertia of a cylinder about its base
added 18 characters in body
Jul
31
comment Moment of inertia of a cylinder about its base
To define the inertia tensor you need $$I= \int \begin{pmatrix} y^2+z^2 & - x y & - x z \\ - x y & x^2+z^2 & -y z \\ -x z & -y z & x^2+y^2 \end{pmatrix} \,{\rm dm}$$ most of the terms fall out for a symmetric shape. This is a result of the vector form of the parallel axis theorem ${\rm d}I = -{\rm d}m [\vec{r}\times][\vec{r}\times]$.
Jul
31
revised Geometry in diagonal matrix and inertia tensor
Fixed typo in element [2,2] of mass moment of inertia tensor
Jul
31
comment Moment of inertia of a cylinder about its base
Related: physics.stackexchange.com/a/111081/392
Jul
31
comment Moment of inertia of a cylinder about its base
@Fadi the parallel axis theorem has to do with calculated mass moment of inertia about an axis away from the center of mass. Here the end axis is $\frac{L}{2}$ away from the COM. I mentioned this because of the definition of the mass moment tensor arises from the parallel axis theorem. See physics.stackexchange.com/a/111081/392
Jul
31
comment How to determine direction of forces in a static problem?
The convention is positive for tension, and negative for compression.
Jul
31
revised Moment of inertia of a cylinder about its base
added 248 characters in body
Jul
31
answered Moment of inertia of a cylinder about its base
Jul
31
comment Moment of inertia of a cylinder about its base
Check the factor in front of the double integral. It should be equal to $\rho = \frac{M}{\pi R^2 H}$ since $I=\int \rho d^2 \,{\rm d}v$ where $d$ is the perpendicular distance from the axis of rotation.
Jul
30
answered Why do we take small steps while walking on ice?
Jul
30
answered Deriving spring oscilation period
Jul
30
revised Deriving spring oscilation period
added 1 character in body
Jul
30
comment Deriving spring oscilation period
Aghh, you should use math formatting for better readability.